ANAEROBIC BACTERIA 173 



sheim, Bac. amylobacter A. M. Bred.) and allied forms found 

 in great abundance in practically all soils. This organism 

 or group was classified by Bergey as CI. butyricum Prazmowski 

 and by Lehman and Neumann as Bac. pastorianus (Winograd- 

 sky). 57 Its physiology and occurrence in the soil is discussed 

 elsewhere (p. 110). 

 (b) Bac. welchii Migula (Bac. aerogenes capsulalus Welch and Nutall, 

 Bac. perfringens Veillon and Zuber, Bac. enteritidis sporogcnes 

 Klein), a short rod 4 to 8 by 1 to 1.5/u, single or in pairs; non- 

 motile, forming oval, central or excentric spores; encap- 

 sulated (No. 44, PI. IX). Found repeatedly in the soil and 

 in sewage. 58 



2. Bacteria decomposing pectins. 



(a) Bac. amylobacter group, which includes the Clostridium pastor i- 



anum (same as la). The forms causing the retting of flax 

 have been described under various names. Here belong the 

 Plectridium of Fribes and Winogradsky, the Clostridium of 

 Behrens, the Plectridium pectinovorum of Stormer, the 

 Granulobacter pectinovorum of Beijerinck and van Delden. 19 



(b) Bac. felsineus Carbone. 



3. Bacteria decomposing celluloses: 



(a) Anaerobic bacteria decomposing celluloses at ordinary temper- 



atures. Here belong the hydrogen and methane organisms 

 of Omeliansky and the Bac. cellulosae dissolvens Khouvine. 



(b) Thermophilic cellulose decomposing bacteria — Clostridium ther- 



mocellum Viljoen, Fred and Peterson. The occurrence and 

 isolation of these organisms is described elsewhere (p. 202). 

 II. Bacteria acting primarily upon proteins: 

 1. Strongl y proteolytic forms: 



(a) Bac. sporogenes Metchnikoff (No. 58, Pi. X), a motile, flagellated, 

 gram positive bacillus, with rounded ends, 3 to 7 by 0.6 to 

 0.8m,* one of the strongest proteolytic bacteria known; it de- 

 composes proteins with the formation of gas, a darkening 

 of the medium and production of a pronounced odor; the sub- 

 terminal spores are formed readily. Found abundantly in the 

 soil, manure, street dust and sewage. 



67 Further information on the classification of the anaerobic bacteria acting 

 primarily upon carbohydrates is given by Donker, H. J L. Bijdrage tot de 

 kennis der Baterzuur — , Butylalcohol — en Acetongistingen. Delft. 1926. 



68 Klein and Houston. Rept. Med. Officer, Local Govt. Board, London, 1898- 

 1899, 318; Greer, F. E. Anaerobes in sewage. Amer. J. Publ. Health, 15: 860-867. 

 1925. 



69 Ruschmann, G., and Ravendamm, W. Zur Kenntnis der Rosterreger Bacil- 

 lus fehineus Carbone und Plectridium pectinovorum [Bac. amylobacter A. M. et 

 Bredemann). Centrbl. Bakt. II, 64: 340-394. 1925. 



